They are like America. When everything is smooth, they appear pretty cool, but when the going gets tough, they fall apart. Right now South Korea is not in an enviable place. It is laden with overwork culture, left vs right, male vs female hatred and the lowest fertility rate in the world. There is also no hope or direction for the country. What are they fighting for? Koreans are generally a hard-working, high achieving people, but there just too few of them with too few resources to achieve stand-alone greatness so they are standing "tall" on a house of economic and foundational science cards they earned by kneeling to America. It's where China would be under the KMT, but you will never become number 1 that way.
The answer you received is very correct (but it is only one part; I will touch on the other aspects below). As a rival to America and the West, China is often demonized so that Americans default to a negative stigma and do not truly explore the contents of Chinese media. They think it's nothing but communist brainwash. But this can only hold for so long as Western power eclipses Chinese power. When that is not true, as we see now, Chinese light starts to shine through the edges and cracks as Chinese pop culture gains popularity worldwide.
Look at North Korea and look at Detroit; which is the prison? LOL
Because Hong Kong, just like South Korea, bows to Western power rather than confronting it. You see a pattern here?
It is starting to do so but will explode once the US is displaced and no longer able to control media to suppress the growth of Chinese culture worldwide.
Nahhh, I'm sorry but it's your inability to think that we don't like about you.
We did. Sign a deal with the devil and the immediate rewards will come but your future is gone. Not that South Korea had any ability to compete with the US; this is China's deal that we turned down. South Korea's deal is to be a helpless lapdog to the US in order to be viewed as harmless, and that drops people's guard, allowing them to be liked. It's just like Japan. Do you think Japanese culture was popular and seem positively in the US during WWII or before? No; it all blew up once Japan bent both knees and it was no longer a threat, allowing it to be harmless and thus likeable.
So I will touch upon the other aspects that have kept Chinese media culture consumption much mlower than Korean media culture consumption worldwide.
Another factor is relatibility. Korea's struggles are fairly normal for what developed countries face, but China's struggles are not relatable to these countries. China's struggles are about how to develop from a poor backwards country into a challenger to the world throne on your own talent under suppression from the lone superpower. Westerners and other countries on their knees don't relate to this; they are told that it is a struggle of evil to break international law and order. When they see the enemy in Chinese films defeated, they watch with the bitterness that that enemy is them! So how can they enjoy Chinese media?
Finally, I can also say that China is an extremely STEM-focused society because the mantra of the nation is the become strong with technology so as to never suffer unfairness again. So Chinese culture has it that the best talents are all invested in STEM; it's a sign of stupidity in China, particularly in the older days, to not study STEM. Only those who are not so smart take up artistic majors. South Korea, on the other hand, has a much more artistic culture, delegating a huge portion of its talent to performance arts. Culturally, being an actor/actress is seen as the holy grail in Korea similar to how Chinese people see a top engineer/scientist. As China becomes more modern and the threat of technological backwardness is defeated, China is becoming more artistic, and thus we see a corresponding rise in Chinese dramas/games/shows worldwide, but it is in its infancy compared to South Korea.
That's in technology, not so much culture.
Your question is not whether all countries are the same; your question is why Chinese media is not as popular as Korean so the answer is given to you. The world is filled with talentless schmucks not worth the hairs off a rat's ass but China and Korea are not among those countries.
Not on their own. They obediently stood on the fundamentals given to them, and given they are very smart people compared to the world average, but not to China, it's a recipe for being a well-fed fat and happy lapdog. But the ceiling to their development is their master. America's not just not stopping them; America rewards them for their obedience and those are big rewards considering how small South Korea is.